Low surface energy materials have proven useful in many applications, including non-wetting fabrics, smart surfaces, membranes, ice-phobic surfaces, as well as anti-fouling surfaces and coatings. Fluoroalkyl polyhedral oligomeric silsesquioxanes (hereafter referred to as “F-POSS”), having surface energy values, γsv, of about 9.3 mN/m, have emerged as promising materials for these types of applications.
While the addition of F-POSS to polymers often yields superhydrophobic and superoleophobic material properties, the production of the superhydrophilic or superoleophobic surface depends on the selection of the polymer matrix. For example, the lack of covalent bonding between F-POSS molecules and spun cast films demonstrate poor surface robustness and are susceptible to surface abrasion. F-POSS also exhibits limited solubility in non-fluorinated solvents, thereby limiting the types of polymer solvents. Short chain (trifluoropropyl) F-POSS compounds have been covalently attached to polymer chain ends through functionalization of the incompletely condensed cage; however, layers comprising these F-POSS compounds do not demonstrate low surface energy property enhancement.
Reactions of long chain F-POSS disilanol compounds with a variety of dichlorosilanes have resulted in a series of functional F-POSS compounds having an increased solubility in organic solvents while retaining low surface energy properties. Moreover, the resultant functionalized F-POSS compounds are covalently bonded to the host substrate, polymer backbone, or surface, which leads to a more mechanically stable and abrasion resistance material. One particular exemplary compound, methacrylate based F-POSS macromere (“MA-F-POSS”) has been shown to produce methyl methacrylate (“MMA”) copolymers with limited control of molecular weight and polymer optical interconnect via traditional azobisisobutyronitirle (“AIBN”) initiated free radical polymerization.
However, there remains a need for improved methods of synthesizing F-POSS-centric copolymers while affording enhanced control of molecular weight, desirable polydispersity indices, and low surface energy properties.